Depositing device for plastic materials



H. T. HALLGNE-LL; JR

DEPOSITING DEVICE FOR PLASTIC MATERIALS Filed Dec. 1, 1943 3 Sheets-Sheet l qifi; 2;. 3947. T HALLQWELL, JR a lfififig DEPOSITING DEVICE FOR PLASTIC MATERIALS Filed Dec. 1, 1945 3 Sheets-Sheet 2 Sept? 2, 1947. H. TJHALLOWELL, JR zfizgpgfig DEPOSITING DEVICE FOR PLASTIC MATERIALS Filed Dec. 1, 1943 I 5 Sheets-"Sheet 3 7 frwezzfir fi mraif I I I Patented Sept. 2, 1947 pEPosrriNG DEVICE FOR PLASTIC MATERIALS Howard Thomas Hallowell, In, enkintowii, Pa., assignor to Pennsylvania Manufacturing Com-- pany, J enkintown, Pa

ware

., a corporation of Dela- Application December 1, 1943, Serial No. 512,513

16 Claims.

of plastic materials in general.

In the attached drawings,

Fig, 1 is a side elevational view of a depositing machine made in accordance with my invention;

Fig. 2 is a section on the line 2-2, Fig. 1;

Fig. 3 is a section on the line 3-3, Fig. 1;.

Fig, 4 is a fragmentary vertical sectional view illustrating details of the depositing elements;

Fig.5 is a section on the line 5.5, Fig. 1;

Fig. 6 is a fragmentary top plan view on a portion'cfthe device shown in Fig.

,Fig. 7 is a section on the line I-1, Fig. 5;

Fig. 8.is a view in perspective of 'a primer head onto which the wax has been deposited by the machine forming the subject of my invention, and, w 7

Figs. 9 to 13 inclusive are fragmentary sectional views illustrating the mode of operation of the depositing device. e 1. a b With reference to the drawings, the primer head illustrated in Fig. 8 consists of a threaded casing l within which, as shown in Fig. 4, is mounted a percussion element 2, a firing pin 3, and amp 4, the latter functioning to retainrthe firing pin in position. To this end, the upper end of the cap 4 is flanged inwardly, as indicated at 5, so as'to overlie the edges of the pin 3. The primary function of the machine forming the subject of my, invention is to deposit wax in the form of an annulus 6, see Fig. 8, around the inner edge of the flange 5 so as to seal the joint between this flange and the firing pin surface and to thereby exclude moisture from the interior of the casing I.

The depositing device, per se, which is best illus- I trated in Figs. 4 and 9 to, 13 inclusive, consists of a casing 1 which is mounted for vertical reciprocation, as hereinafter described, and which has in the interior thereof a cylindrical bore 8 for reception of a plunger 9, this plunger being adapted for reciprocation in and with respect to the said casing. The plunger 9 is provided with a longitudinal passage I I which terminates in a threaded countersunk recess and in assembly this 'rec'ss receives'the correspondingly threaded end of a hollownozzle element I2. The elementl 2 extends downwardly through a cylindrical bore [3 into a recess I i extending upwardly from a port I0 the lower end ofthe' casingl', therecess I i being ofgsomewhat greater diameter than the diameter of the element I2 sothat a space is left between the inner wall surface of the recess I4 and the outer surface ofthe said element. The interior channel I5 of the element I2, which communicates with the channel II of the plunger 9, communicates'also with the recess I4 through ports It in the wall of the element. Below the ports I6 the element I2 has an extension H the lower end of whichprojects through the port In and is shaped toiconstitute a closure for said port. The wall, of the. port I0 is beveled outwardly as indicated at I8 and the closure end I9, of the extension, I1 is correspondingly beveled, these beveled surfaces being adapted to meet when the plunger is retracted to thereby effect a positive cut-off of the port III. ,When th plunger 9 and its extension I2-are occupying the positions shown in Fig. 4, theport I0 is open, but when the plunger 9 is elevated or retracted the port I0 is progressively closed,vand it will be noted also that as the plunger is retracted, the bevel 22 is caused to enter the recess I4 witha consequent reduction in the interior size of the recess; such reduction continuing until the beveled surfacesmeet to positively close the port. 2 Y 7 7 In effect, the channels II and l5 and the recess I4 constitute together a container for the wax or other plastic material. The plunger 9 with its extension I 2 and terminal portion I 9 constitute in effecta-retractable closure for the open lower end or discharge port II] of the container and this closure member'has in effect an entrant portionwhich moves into the container as the member advances toward the operative port-closing position. If under these conditions the container is full of the waxfthe saidentrant portion will have-theeiiect of extruding asmall part of the contents of the container from'the port II) so that when the end I9 of the closure member makes contact with the lip of the port as described above, the extruded portion is positively cut off from the main body of the wax in the container.

In practice, provision is made for bringing the housing I into engagement with the end of the priming head I after the manner illustrated in Fig. 4,so thatthe waxextruded 'andcut off as described will be deposited at the inner surface of the flange 5 and over thejoint between this flange and the element 3 of the primer head. This action is best illustrated in Figs. 9 and 10. g 9, the elements'are illustrated in positions which they assume 'immediately'before the extruding operation and it will be noted that the wax indicated by the reference numeral 2| completely fills the recess I4 around the extension I1 and extends downwardly between the beveled surface l8 and the opposite beveled surface of the head element l9. As the plunger 9 is elevated in the housing 7 and the aforesaid beveled surfaces approach each other the wax 24 is extruded, as illustrated in Fig. 10; this extrusion resultin from the entrant portion 22 of the head [9 which enters and thereby reduces the capacity of the container. The extrusion of the wax continues until the aforesaid beveled surfaces contact each other at which moment the extruded portion of the wax is cut off from the main portion which remains in the container. This is shown in F g. 11 and it will be noted by reference to Figs. 10 and 11 that in the extrusion operation wax is directed by the beveled surfaces into the angular corner between the flange 5 and the top surfaceof the firing pin 3, the deposited wax being in the form of a continuous annulus which seals the joint between these elements. Subsequentlyfthe casing 1 is retracted, as shown in Fig, 12, with the closure member still in the positive port closin position thereby leavin the deposited annulus of wax, designated in Fig. 12 by the reference numeral 23, in the desired sealing position. As the re tractive movement of the casing continues the plunger 9 is moved with respect to the casing so as again to open the port In, and while in this position the mechanism hereinafter described functions to replenish the material previously extruded from the container so that in the next operation the. device may function as described above to deposit the wax on a succeeding primer head.

Referring now to Fig. 1, the 'casing 1 is mounted for vertical reciprocation in a suitable'fixed frame 25, the casing being supported in the frame in 'a position overlying the peripheral edge of a rotary dial or work table this dial having in its peripheral portion a concentric series of sockets 21 for reception of the primer heads I. By movement of the dial, theprimer heads may thus be brought successively intoposition under the depositing device and in vertical alignmentiwith the casing 1 and the associated depositing elements previously. Q SP ib QP. V.

The required verticalreciprocatory movement of th casing fljiseffected in the present instance through the medium of a rack 28, anda segmental ear 29 which meshes with the rack and which is formed at one end of a l ever 3l pivoted at 3; to the frame 25, The other end of the lever 3| is bifurcated and the bifurcations 33--33, see Figs. 1 and 2, lying at opposite sides of a threaded stem 34, engage the under surface of a collar 35 which is threaded on the stem 34 as illustrated and which issecured in adiusted position to the stern bymeans ofa set screw 36. The bifurcated end of the lever 3| is held against the underside of the sleeve 35 by means of a spring 3'I which embraces the rod 34 and which seats upon a boss 33 on the frame which boss functions also'as a guide for the rod 34, and the upper end of the spring supports a flanged sleeve 39 which is slidably fitted on the rod 34 and which engages the under side of the bifurcations of the said lever. The spring therebyfunctions through the lever to support the rod 34 in a relatively elevated position. The lower end of the rod is secured to one arm 4| of a bell-crank lever 42 pivotally supported in the fixed frame, and the other arm 43 of this lever carries a roller 44 which engages a cam 45 on a cam shaft 46 journaled in the lower part of the frame. As shown in Fig. 2, this shaft is provided with a gear 41 by means of which it may be connected to a suitable source of power. It will be noted that the spring 37 functions to hold the roller 44 in operative engagement with the associated The cam 45 functions to periodically vertically reciprocate the housing 1.

The vertical reciprocation of the member 9 in and with respect to the casing I is effected through the medium of a lever 48 which is pivoted at 49 on a bracket 51 at the upper end of the casin 1. The upper end of the lever .48 is bifurcated as indicated at. 52 in Fig. 3 and these bifurcations encag in recesses at opposite sides of a sleeve 53 wh is threaded on the upper end of the member '9, as shown in Figs. 1 and 3. The set screw 54 looks the sleeve 53 in adjusted position on the member. The other end of the lever 48 extends downwardly and has at its lower end a roller or block '55 which fits into a vertical slot 56 at the upper end of a secondlever 51. This latter lever is pivoted at 58 to the frame and the lowerend theredf carries'a' roller 59 which engages a cam 61 on' the cam shaft-.46. Thecam 5| functions to oscillate the lever 51 which in turn oscillates the lever "48, the oscillations of this "lever being converted into vertical reciprocations of the-member 9.

Referring to Fig. 4-, it is to be noted that the upper end of the channel H of the member'S communicates with a duct 62, the terminal end of this duct being threaded into the member 9 and extending inwardly through a slot 63 in the casing "l. The ductfG'Z, which is flexible, extends to a pump and valve housing '64 secured in the frame'25 as illustrated. The duct 62 communicates with a port 65 which is controlled by a rotary valve 66, an d this valve also controls a second port 61 to which is connected a duct 68. The valve (i6 has two ports 69 and TI which are arranged for communication respectively with the ports '55 and 61, and as'shown in Fig. 7 the arrangeinent of the ports 69 and H is such that when one of these ports communicates with its associated port 65 or'6'7. the other of the ports 69 and "H is closed. Thus in Fig. '7 ports H and 61 are in communication with each'other, whereas the ports 59 {and 65. are disconnected "and sealed by the valve 66, or the valve housing as the case maybe. 7 Both' of thepGrts'B'B'and Tl connect with a commcn'centra'l. axially extendin port 12 which, as shown in 5, constitutes a cylinder for a plunger 13. This plunger is secured to a crosshad l4 slidably mounted in a'suitable bore 15 in'the interior of the va1ve"6'6. Reciprocatio'n of tne'crcssne diseifected through the medium of the "beucrank lever 16 Which is pivoted at T! to the housing scene arm of thislever extendin through the wall of the recess of the bore 'l5 into operative engagement with the crosshead I4, and the other end being connected through a rod 18 to'a lever 19, this level being mounted on a pivot pin '81 in the frame and being operatively connected through a roller "82 with a cam 83 on the shaft 46. Aspring8'4 at'the upper end of the lever 1'9 has its other are connected to the frame 25 and 'exrt's resilient pressure tending to-maintain the lever into operative enga ement with the cam.

The cam operates to oscillate the lever and thrdu'ghtlie rod 18 and the lever 16 to reciprocatethe'pltinge: 13. A spring 85in thebotto m of the bore 15 iexrtsre silient pressure onthe inner end of the crosshead 14teri'ding to force the crosshead with its plunger 13 outwardly and into engagementwithan adjustable stop 85 in the outer endof thevalve' housing. 7 I

Oscillation of the valve 66 and selective connection of the port 65 and 61 with the cylinder 12 is effected through the medium of a valve cap 81 which in effect forms a continuation of the housing 64 as illustrated in-Figs. 5 and 6 and which is secured to the outer end of the valve 66 by means of a set screw 88. A rod 89 has its upper end attached to the cap 81 as illustrated in Fig, 6, and this rod extends downwardly and connects at its lower end with a bellcra-nk lever 9|, this lever being pivotally supported on the pin 8| and being operatively associated with a cam 92 on the cam shaft 46. A spring 93 attached to the upper end of the lever 9| and connected at the other end to a pin 94 on the frame 25 exerts resilient pressure tending to maintain the lever 9| in operative engagement with the cam 92. The cam operates to oscillate the lever 9| and to thereby longitudinally reciprocate the rod 89, and this reciprocation of the rod 89 effects in turn an oscillation of the valve cap 81 and therethrough of the valve 66. In one position of oscillation the port 61 is connected with the port H as shown in Fig. 7, and in another position of oscillation the port 65 is connected with the port 69. When the ports 61 and H are in communication with each other the plunger 13 is timed for its retraction stroke whereby wax or other plastic material, to a source of which the duct 68 is eCOnneCted, is drawn through the duct and through the ports into the cylinder 12. When the port 65 is connected with theport 59 the plunger 73 is advanced with the result that the wax previously drawn into the cylinder 12 is ejected through the port 65 and duct 62 to the channel I I of the member 9 as previously described. The, pump is constituted so that the quantity of wax injected at each stroke corresponds to that ejected or extruded in each stroke of the plunger 9, and the elements are timed so that each extrusion is followed by a replenishing stroke of the pump. Exact synchronization of the several moving elements is obtained through the use of the common cam shaft 46.

In regard to the operation of the device, the cycle of movements of the casing 1 and plunger 9 has been set forth on pages land 5-supra. The elements of the pump and the distributing valve 66 are operated in timed relation to the movements of the casing l and plunger 9 through the medium of the associated cams on the shaft 46. Thus during the period When the said casing l and plunger 9 are passing through the stages illustrated in Figures 9 to 12 inclusive, the pump plunger 13 and valve 66 will be actuated to draw a charge of wax from the source into the cylinder I2; and when the casing I has moved to the position shown in Figure 13 and the plunger 9 is in a depressed position as indicated inbroken lines, the pump plunger 3and valve 96 will be actuated to force the said charge into the duct 62 so as to replenish the wax discharged by the previous retractive movement of the plunger 9 as in Figure 11. It will be understood that the wax is of a viscous consistency which precludes escape from the casing by gravity flow when the plunger 9 is depressed.

For cleaning and primin purposes, means has been provided for directly connecting the ports 65 and 61, as shown in Figure'l. A by-pass (5'! is provided from the port 61 so that when the valve 69 is in a position in. which the port 69 registers with the port 65, the port 1 [will register with the innerend of the by-pass. q'I'he byepass channel is normally closed by a valve 'lfl which may be adjusted from the outside of the housing (see Figure 2)- to open the by-pass when required. With the by-pass open, the entire system may be either charged with or cleared of wax by suitable pressure means applied by way of the port 61.

I claim:

1. In a device for depositing plastic materials, a constant-volume container for said material having a discharge port, a member constituting a retractable" closure for said port, said member having an entrant portion movabl into the container as the member advances toward the operative position with respect to the port so as to extrude material from the container, and means for advancing and retracting the closure member.

2. In a device for depositing plastic materials, a constant-volume container for said material having a discharge port, a member constituting a retractable closure for said port, said member having an entrant portion movable into the container as th member advances toward the operative position with respect to the port so as to extrude materia1 from the container, and being engageable with the lip of the port when in the said operative position so as to efiect a positive cut-ofi of the said'extruded material, and means for advancing and retracting the said member.

3. In a devicefor depositing plastic materials, a container for said material having a discharge port, a member constituting a closure for said port and means for advancing and retracting the member to open and close the port respectively, said member having an entrant portion movable into the container as the member moves toward the port closing position so as to extrude material from the container, and being engageable with the lip of the port when in'the said port closing position so as to effect a positive cut-01f of the said extruded material, and means synchronized with the movements of the member and operative when the member is in retracted position for charging the container with measured quantities of said material.

4. In a device for depositing plastic materials, a constant-volume container for said material having an opening, a member constituting a retractable closure for said openingsaid member in retracted position defining the inner peripheral edge of a narrow endless port the outer peripheral edge of which is defined by the Wall of said opening, said member in the operative position seating on said wall and having an entrant portion movable into the container as the member advances toward said operative position so as to extrude material from the container in an endless band, through said port, and means for advancin and retracting the closure member.

5. In a device for depositing plastic materials; a constant-volume container for said material. having a circular opening, a member constituting a retractable closure for said opening and havinga circular portion which when the member is re-- tracteddefines the inner peripheral edge of an annular port the outer peripheral edge of which is defined by the wall of said opening, said member in the operative position seatin on said wall and having an entrant portion movable into the container as the member, advances toward said operative position so as to extrude material from the container in an annular band through said port, and means for advancing and retracting the cloure ember.

6. Ina. device, for depositing plastic materials, a casing of constant volume having aportyan'd a plunger mounted, for reciprocation in thecasing and; projecting loosely through-the port;- so; as to P vide a passage for discharge or said, plastic material from inside the casing, said I plungerhaving a terminal portion adapted whenv the plunger is moved inwardly of the. casing to enterand tov subsequently seat against the Wall of said port so as to close the latter; said terminalaportion .being' thereby operative to; extrude said. material: in predetermined quantity from the. casing.

'7. In a device for depositing plastic. materials; a casing of. constant volume having a por.t:,. plunger mounted for reciprocation in; the cast.- ing and projecting loosely through'theportso as to provide a passage for dischargeof; said plastic material from inside the casing saida plunger having a terminal portion adapted when the plunger is moved inwardly of the casingxtolenter and to subsequently seat against the wall of: said port so as to close the latter, said. terminal portion being thereby operative to' extrudea said ma terial in predetermined quantity from. the casing; 8. In a device for depositing plasticrmaterials, a constant-volume container forsaid, material having a circular opening, a member constituting a retractable closure for said opening: and having a circular portion which when the member'is retracted definestheinner peripheral edge of an annular port the outer peripheral edge of which is defined by the wall of said opening; said wall being outwardly beveled and forming a seat for a corresponding bevel. on the end of said memher, and the beveled surface of said member projecting intosaid port whenthe member is in the seated position so as to effect-anextrusion' of said material from the port when the member is moved toward the seating-position, and means'for advancing and retracting the closure member.

9; In a device for depositing plastic materials, a casing having a port, a plunger mountedfor reciprocation in the housing and projecting loose 1y through the portso as toprovid'e a passage-for discharge of said plastic-material frominside the casing, said plunger having a terminal portion adapted when the plunger is moved inwardly of the casing to enter and to subsequently seat against the wall of said port so as-to close the latter, said terminal portion being therebyoperative to extrude said material from the casing, means for reciprocating said plunger-in the casing, and means synchronized with-thereciprocatory movement of the plunger for maintaining a constant supply of material inthecasing,

10. In a device for depositing plastic-materials, a reciprocatory casing having a port, a plunger mounted in the casing for reciprocation in the casing and projecting loosely through the port so as to provide a passagefor discharge of; said plastic material from inside the casing; said plunger having a terminal portion adaptedwhen the plunger is moved inwardly of the; casing to enter and to subsequently seat against the wall of said port so as to close the-latter, said'terminal portion being thereby operative to extrude said material from the casing; means for reciprocating the casing and for synchronously reciprocating the plunger in and with respect to' the casing, and means for replenishing the supply of material in the casing after each extrusion operation; 11'. In a device for depositing plastic materials; a casing havinga port, a plunger mounted-for reciprocation in the casing and projecting loosely through the port so as to provide a passage for discharge ofsaid. plastic. materialifrom inside the casing, saidplunger having a longitudlnally: ex-- tending bore/communicating at one-end:witl1 the interior of the casing and said plunger having a terminal portion. adapted when theplunger is moved inwardly'of the casinglto-enter and to subsequently seat. against the Wallof said portv so as to close the latter, said terminal portion being thereby operative to extrude said material from thecasing, meanstior reciprocating the plunger, a duct; attached to said plunger in communication with the-said bore and movable with the plunger, and" means connected to said duct operating in synchronism with the movements of the plunger for: replenishing the material extruded from the casing.

12;. In a device for depositing plastic materials; acontainer for said: material having a discharge port,. a; member constituting a retractable; closure forxsaid'; port, saidmember'having, an entrant portion movable" into the. container as the. member advances toward the operative; position with respect. to-theport soas to extrude'a. predetermined quantity of the material from: the container, means: for advancing: and retracting the closure member, and means operating in synchronism with the movements of saidmember for injecting into. the container measured quantities of said material: while the closureis in. said operative position.

13. In' adevice fordepositing wax-inthe end of a .priming'head, a casing having aiport andishaped around said port to fitthe said'end of the. priming head, a. plunger mounted for reciprocation in' the casing and'projecting loosely through theport so astoprovideapassage for discharge of the: said plastic material'- from. inside the: casing, said plunger: having a terminal-portion adapted when the plunger is moved inwardly of the casing to enter and to subsequently seatagainst the wall of said port so asto' close the latter; said terminal portion being thereby operative to extrude said materi'alfrom the casing upon the end surface of said priming head, and means-for advancing and retracting the said plunger so-as .to periodically open and close the port.

14. In a device for depositing plasticmaterials, a frame, a casing mounted for reciprocation in said frame and having a discharge port; a plunger mounted for'reciprocation in and with respect to the casing and projecting loosely-through the port so as-to provide a passage for discharge of said plastic material from inside the casing, said plunger having-a terminal portion adapted when the lunger is moved inwardly of the casing to enter and to subsequently seat against the wall of said port so as to close the latter, said" terminal portion being-- thereby operative to eXtrud'e said material fromthe casing, means for individually and synchronously reciprocating the casing and the plunger, and means for maintaining a constant supply of the materialin the casing.

15. In a device for depositing plastic materials, a' frame, a casing mounted for reciprocation in said 'frameand having a discharge port, a plunger mounted for reciprocation in and with respect to the casing andprojecting loosely through the port soas to provide a passagefor discharge of said plastic material from inside the casing; said plunger having a terminal portion adapted when the plunger is moved inwardly ofthe; casing to enter and tosubsequently seat against the wall of said port so-as to-close the latter, saidterminal portion being thereby operative to extrude said material from. the casing, means for individually and synchronously reciprocating. the casing and the pl'ungen. and means for maintaining a conthe casing and projecting loosely through said port, said plunger having a terminal portion adapted when the plunger is moved inwardly of the casing to seat against the wall of said port and to close the latter, a cam shaft, and independent means for operatively connecting the cam shaft to the casing and to the said plunger, the said connecting means for the plunger comprising a 10 lever pivotally attached to the casing and movable with the latter, and a second lever slidably connected with an arm of the first named lever and operatively connected to the cam shaft.

HOWARD THOMAS HALLOWELL, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,324,455 Keimetal July 13, 1943 2,337,740 Albright Dec. 28, 1943 2,123,354 Corse July 12, 1938 2,208,636 Johnson July 23, 1940 2,265,632 Gorlitzki Dec. 2, 1941 

